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31.
文中利用TRMM卫星测雨雷达探测反演的云水、雨水、云冰和降冰4种云参数产品及实况降水资料,对比检验该人工增雨云系业务模式对云微观场和地面降水场的预报能力.结果表明,人工增雨云系模式系统对降水的预报能力要略优于现行业务运行的GRAPES模式;人工增雨云系模式系统能较好地预报云系系统云物理微观量的垂直结构特征,模式预报的微观场与卫星监测吻合较好;在播撒窗区的水平分布上,模式预报的各水凝物分布形势和强中心位置与卫星监测一致,其大小也接近监测值;人工增雨云系模式能较好地预报云的微观场和天气形势场,可作为云系人工增雨条件决策的重要参考依据.  相似文献   
32.
热带降水测量卫星(TRMM)上搭载的测雨雷达是第一部能够提供三维降水信息的星载雷达,机载雷达也能够对降雨进行实时观测。由于机载和星载雷达观测有很多共同点,所以选择机载、星载雷达数据进行对比。1998年8月26日NOAA/P3飞机对Bonnie飓风进行了一次观测飞行,与此同时TRMM卫星也同步扫过该区域,因此利用对Bonnie飓风的机、星观测数据对应点数值对比、差值对比、平均值对比等,对Bonnie飓风做了进一步分析。对比结果一致,印证了TRMM数据的可靠性,同时进一步验证了双束立体雷达算法的联合算法的可靠性。  相似文献   
33.
Understanding the spatio-temporal characteristics of water storage changes is crucial for Ethiopia, a country that is facing a range of challenges in water management caused by anthropogenic impacts as well as climate variability. In addition to this, the scarcity of in situ measurements of soil moisture and groundwater, combined with intrinsic “scale limitations” of traditional methods used in hydrological characterization are further limiting the ability to assess water resource distribution in the region. The primary objective of this study is therefore to apply remotely sensed and model data over Ethiopia in order to (i) test the performance of models and remotely sensed data in modeling water resources distribution in un-gauged arid regions of Ethiopia, (ii) analyze the inter-annual and seasonal variability as well as changes in total water storage (TWS) over Ethiopia, (iii) understand the relationship between TWS changes, rainfall, and soil moisture anomalies over the study region, and (iv) identify the relationship between the characteristics of aquifers and TWS changes. The data used in this study includes; monthly gravity field data from the Gravity Recovery And Climate Experiment (GRACE) mission, rainfall data from the Tropical Rainfall Measuring Mission (TRMM), and soil moisture from the Global Land Data Assimilation System (GLDAS) model. Our investigation covers a period of 8 years from 2003 to 2011. The results of the study show that the western part and the north-eastern lowlands of Ethiopia experienced decrease in TWS water between 2003–2011, whereas all the other regions gained water during the study period. The impact of rainfall seasonality was also seen in the TWS changes. Applying the statistical method of Principal Component Analysis (PCA) to TWS, soil moisture and rainfall variations indentified the dominant annual water variability in the western, north-western, northern, and central regions, and the dominant seasonal variability in the western, north-western, and the eastern regions. A correlation analysis between TWS and rainfall indicated a minimum time lag of zero to a maximum of six months, whereas no lag is noticeable between soil moisture anomalies and TWS changes. The delay response and correlation coefficient between rainfall and TWS appears to be related to recharge mechanisms, revealing that most regions of Ethiopia receive indirect recharge. Our results also show that the magnitude of TWS changes is higher in the western region and lower in the north-eastern region, and that the elevation influences soil moisture as well as TWS.  相似文献   
34.
以黄淮海平原为研究区,基于59个气象站点的逐月降水数据,采用相关系数(R)、相对误差(BIAS)和均方根误差(RMSE)对TRMM 3B43降水产品的精度进行系统评估,揭示黄淮海平原降水的时空变化规律。研究表明:① TRMM 3B43产品对研究区内大部分气象站点存在轻微高估现象,总体上TRMM产品和站点数据在黄淮海平原的拟合效果较好,且月尺度的精度较年尺度高;② 1998—2016年黄淮海平原年降水和秋季降水增加明显,其余季节降水呈不同程度的减少趋势;③ 研究区降水在空间上呈从南到北递减的趋势,且南北降水差距较大。研究结果为卫星降水产品在中纬度地区水资源评估、农业生产和洪旱灾害等研究提供一定的参考。  相似文献   
35.
青藏高原对全球气候研究具有重要意义,而降水数据对水文、气象和生态等领域的研究也至关重要,且随着研究内容和尺度的变化,对高时空分辨率的历史降水数据的需求越发迫切。本文基于TRMM 3B43降水数据,采用随机森林算法,引入归一化植被指数(AVHRR NDVI)、高程(SRTM DEM)、坡度、坡向、经度、纬度6个地理因子,建立历史降水重建模型,获得1982-1997年分辨率为0.0833°的青藏高原年降水数据,然后根据比例系数法计算出月降水数据。为提高精度,利用站点数据对月降水数据进行校正。结果表明,该方法能简单有效地获得高时空分辨率的历史降水数据,决定系数R2大部分在0.4~0.9之间,平均值为0.6767,其中夏季效果最好,冬季效果最差;均方根误差RMSE和平均绝对误差MAE均在50 mm以下,RMSE均值为22.66 mm,MAE均值为15.97 mm;偏差Bias较小,基本在0.0~0.1之间。  相似文献   
36.
In this study, the micro- and macro-physical properties, thermal structure and precipitation characteristics of cyclone eye walls and their surrounding spiral clouds were analysed with CloudSat and TRMM data for five tropical cyclones (TCs) in 2013. The results show that the ice-phase clouds of a mature TC are mainly above 5 km. With increasing altitude, the cloud droplet effective radius decreases, and the particle number concentration increases. Ice water content first increases and then decreases with increasing height. In the eye area, in addition to the well-known warm-core area, another warm core is also apparent around the eye at a height of 8 to 15 km. The horizontal distribution of precipitation is characterized by large-scale stratiform precipitation mixed with independent convective precipitation. The height of precipitation is mostly below 7.5 km, and the heavy rain is mainly below 5 km. When the peripheral convective clouds are strong enough, ice particles would be generated, thus providing conditions that are favourable for the formation of precipitation below.  相似文献   
37.
史岚  万逸波  张狄  王茜雯  杨娇 《气象科学》2018,38(5):616-624
以2001—2010年中国地面自动站降水资料为基准,对中国大陆范围内CMPA(CMPA_Daily)降水资料进行精度评价研究,并与CMORPH1.0(CPC MORPHing technique gauge-satellite)、TRMM3B43V7(Tropical Rainfall Measuring Mission 3B43)降水资料精度进行对比,并进一步结合高程、坡度、坡向、坡向修正因子分析地形因子对数据质量的影响并探讨不同地貌类型下数据的精度。结果显示:CMPA在年、月尺度上均能较好地反映降水的多寡,与站点实测数据具有较高的相关性,误差波动较为平稳,数据质量及稳定性优于CMORPH与TRMM;从时间序列曲线显示CMPA的精度呈现较为明显的季节性差异,均方根误差夏季高于冬季,相关系数、百分比偏差、平均相对误差冬季高于夏季,总体而言CMPA夏季的误差高于冬季,由于夏季降水的基数大而导致了百分比偏差以及平均相对误差较低;分析地形的影响表明,高程、坡度对数据质量的影响大于坡向与坡向修正因子;在复杂地形下,高海拔与高坡度地区CMPA精度均有所降低,但降水资料的精度仍然优于CMORPH与TRMM。  相似文献   
38.
利用16 a的TRMM卫星观测资料,分析了亚洲季风区准圆状、线状和拉长状中尺度对流系统(MCSs)的空间分布、对流属性及其区域变化特征。结果表明:拉长状MCSs的数量最多,准圆状的其次而线状的最少。自西向东,准圆状(线状)MCSs数量占各区域MCSs总数的比例逐渐减小(增加),线状MCSs在副热带和洋面地区的产生几率相比更大。MCSs的发生频次呈现以暖季(5—9月)为峰值的单峰分布,准圆状和拉长状MCSs的暖季峰值比线状MCSs的大。MCSs主要发生在下午—傍晚时段,但线状MCSs在午夜—凌晨出现的概率比其它两种大。3种类型MCSs的整体强度基本表现为副热带地区弱于近热带地区,但不同类型MCSs的强度差异在各区域不尽相同,如中国中东部地区和西北太平洋地区的准圆状MCSs强度最强,但东海及其以东洋面的线状MCSs强度最强。  相似文献   
39.
利用2005年9月东亚中低纬地区的63个时次的TRMM卫星资料,分析了降水云和非降水云的红外辐射特征。结果显示:10.8μm通道大部分非降水像元的亮温大于280 K,晴空像元的亮温更高;大部分降水像元的亮温小于280 K,降水越强亮温越低,强降水的亮温在260 K以下。非降水像元的分裂窗通道亮温差(BTD45)总的来说都高于1.5 K;降水像元的BTD45总的来说都小于3.0 K,强降水像元BTD45较低,一般在2.0 K以下。在此基础上,分析了中低纬度夏季6次的不同类型的大尺度短时强降水数据,得到了中低纬度夏季强降水过程中非降水云和降水云对应的红外辐射特征,并以此为依据,提出BTD45为3.0 K和10.8μm通道亮温260 K为降水识别阈值,二者结合,可以得到较好的降水判识结果。  相似文献   
40.
The volumetric rainfall attributed to Hurricane Floyd in 1999 was computed for the bulk of the Tar, Neuse, and Cape Fear River Basins in eastern North Carolina, USA from the Tropical Rainfall Measuring Mission (TRMM) Multi-Satellite Precipitation Analysis (TMPA) research product, and compared with volumes computed using kriged gauge data and one centrally located radar. TMPA showed similar features in the band of heaviest rainfall with kriged and radar data, but was higher in the basin-scale integrations. Furthermore, Floyd’s direct runoff volumes were computed and divided by the volumetric rainfall estimates to give runoff coefficients for the three basins. The TMPA, having the larger storm totals, would suggest greater infiltration during Floyd than the gauge and radar estimates would. Finally, we discuss a concept for adjusting the United States Department of Agriculture Natural Resources Conservation Service rainfall-runoff model when predicting discharge values from real-time TMPA in ungauged river basins.
Scott CurtisEmail:
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